The improved galvanic corrosion resistance of a eutectic high entropy alloy through heat treatment

• Published in: Journal of materials research Vol. 37; no. 23; pp. 4211 - 4221
• Main Authors: Kumar, T. Sudeep, Chauhan, Lakshay, Chakravarthy, K., Chelvane, Arout, T., Shanmugasundaram
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 14.12.2022; Springer Nature B.V
• Subjects: Aluminum; Applied and Technical Physics; Biomaterials; Body centered cubic lattice; Chemistry and Materials Science; Corrosion rate; Corrosion resistance; Electric arc melting; Eutectic alloys; Face centered cubic lattice; Galvanic corrosion; Heat treatment; High entropy alloys; Inorganic Chemistry; Intermetallic phases; Materials Engineering; Materials research; Materials Science; Nanotechnology; Quenching; Room temperature; Eutectic high entropy alloy; Corrosion; X-ray photoelectron spectroscopy (XPS); Structural; Electrochemical impedance spectroscopy
• ISSN: 0884-2914; 2044-5326
• DOI: 10.1557/s43578-022-00787-9

Eutectic high entropy alloys (EHEA) are gaining popularity owing to their high strength and ductility and hence they could be used for structural applications. In this work, an AlCoCrFeNi 2 EHEA was prepared by arc melting and its corrosion behavior was studied at different heat treatment conditions such as annealed at 1100 °C, quenched at 1100 °C, and quenched at 1200 °C. All samples exhibit FCC and BCC phases in different volume fractions. The corrosion behavior of all samples was studied in 3.5 wt% NaCl solution at room temperature. The sample quenched at 1200 °C has shown better corrosion resistance with a corrosion rate of 1.7 × 10 –3  mm/yr. The better corrosion resistance is ascribed to the order-to-disorder transformation of the B2 phase during heat treatment at 1200 °C and the increased distribution of Al content in the FCC phase which results in the formation of a protective passivation layer. Graphical abstract